Method for transfer of data files from a mass storage of a communication device to a post-processing system by using control files

ABSTRACT

A method for transfer of files produced by a communication device from a mass storage of the communication device to a memory of a post-processing system for the files maintains the control file of the communication device by marking it with the information on the state of the files in each mass storage of the communication device, and a time stamp of the latest writing operation into it. This is followed by reading of the control file into a post-processing system, and comparing the file to another control file which is in the memory of the post-processing system and which is updated in each transfer. Reading into the post-processing system of such files of the communication device that have been modified on the basis of the comparison of control files since the latest updating of the control files of the post-processing system. The final step comprises updating of the control file of the post-processing system by marking it with the information as to the files that have been transferred, and copying the information to the communication device for indicating the capacity made available in the mass storage of the communication device.

This application is a national phase of international application PCT/F195 / 00417 filed Aug.7,1995 which designated the U.S.

The present invention relates to a method for transfer of files producedby a communication device from a mass storage of the communicationdevice to a memory of a post-processing system for the data contents ofsaid files.

Digital switching exchanges and similar communication devices produceand are fed with a lot of various kinds of data which are to be storedfor later processing. Such data include, for example, new or changedsubscriber information, charging data of calls, various kinds of alarms,etc. The post-processing procedures include, for example, systemmaintenance, error analysis, charging subscribers, making statistics,etc.

Usually, communication devices comprise mass storages of their own, forexample, a hard disk onto which they store the required data into files.Individual communication devices do not usually perform by themselvesthe post-processing of the data gathered, but it is done in acentralized manner by a separate post-processing system, such as anoperation and maintenance center, to which, through an operation andmaintenance network, the data are gathered and stored by means of a filetransfer, access and management service.

In this case, a problem occurs concerning the free storage capacity ofthe mass storage of the communication device, because without deletingprevious data that has already been sent forward, the memory will verysoon become full. Prior art methods and protocols have required measureson the part of the operator, or include complicated verificationroutines straining system internal signaling channels.

It is the purpose of this invention to create a simple and reliable wayfor transfer of files from a communication device to a post-processingsystem. In order to achieve this, the method of the invention ischaracterized by

maintaining the control file of a communication device by marking itwith information on the state of the files in each mass storage of acommunication device, and/or a time stamp of the latest writingoperation into it;

reading of said control file into a postprocessing system, and comparingit to another control file which is in the memory of the post-processingsystem and which is updated in each transfer;

reading into the post-processing system of such files of a communicationdevice that have been modified on the basis of the comparison of controlfiles since the latest updating of a control file of the post-processingsystem;

updating of the control file of the postprocessing system by marking itwith information on the files that have been transferred, and copyingsaid information to a communication device for indicating the capacitymade available in the mass storage of the communication device.

Other preferred embodiments of the invention are characterized by whatis set forth in the attached claims.

In the following, the invention will be described in closer detail withreference to the accompanying drawings in which FIG. 1 shows a generaloverview of a communication network in which the invention can beapplied, FIG. 2 shows the method of the invention in practice as thefiles are being read and written into.

As an example of a communication device, the Nokia Telecommunications DX200 switching exchange and connection from it to a post-processingsystem is hereby used. It is possible to connect the DX 200 exchanges,marked DX1 -DX4 in FIG. 1, to a DX 200 operations and maintenancenetwork. By means of the operations and maintenance network, theoperation of the exchanges and the gathering of data they produce can becentralized in a desired Operations and Maintenance Center, OMC. Fromthe exchanges DX1 -DX4 or from the OMC (OMCA, OMCB in the figure), it isPossible to arrange a communication link to, for example, apost-processing system of a packet network terminal X.25, marked OS(Operation System) in the figure. The data link is able to transferfiles by a standard protocol, for example, by a FTAM (File TransferAccess and Management, ISO IS8571) protocol.

From any point into which a data link has been installed in theoperations and maintenance network, data gathered in the point can besent to a post-processing system by a FTAM protocol. Thus, thepost-processing system serves as a controller for the FTAM transfer.Within the scope of the invention, it is, however, possible to use anyother standard data transfer protocol, such as a FTP (File TransferProtocol) protocol of a local network, and a TCP/IP local networkinterface.

Switching exchanges DX1 . . . DX4 store the data they gather into filesof standard length in their mass storage devices, for example, on a harddisk. Date, indicating when the respective data files have been writteninto, and the state of the data file are marked into a separate controlfile. The possible states of the data files are:

(1) open, in which case the data file is being written into:

(2) full; and

(3) transferred.

The exchange may comprise several mass storages in which case it ispossible to sort the data to be stored. Disk space according torequirements can be reserved in each mass storage. The disk spaceconsists of a number of data files. As the data is being stored, it isappended to a data file which is open at that particular moment. Thedata is written into this file until it is full after which the storingof data continues in the next file. It is also possible to determine aperiod of time, and when said period of time has lapsed, the data fileis closed and the next file is opened for storing of data.

A control file is also located in the mass storage of the exchange, andit comprises one record per each data file. A corresponding control fileis located in the postprocessing device. It is marked with a dateindicating when each data file has been transferred to the mass storageof the post-processing device, and it does not require any dataconcerning state.

As the post-processing device begins to collect data from the exchange,it first reads the control file of the exchange by a FTAM protocol. Bycomparing the control file it has read to the control file of its own,the postprocessing device infers which data files are full, new, or intowhich ones new data have been written. The selection criteria can beapplied to the files to be transferred so that, for example, only thefiles that have become full are transferred. The post-processing systemreads to itself the files to be transferred by the FTAM protocol. As amatter of fact, according to the invention, no other kind ofcommunication besides the FTAM protocol is required between the systemand the exchanges. After this, the post-processing device marks itscontrol file with information on which data files have been transferred,and writes its control file in the mass storage of the communicationdevice as well. By comparing the control files, the communication devicecan in such a case infer which data files have been transferred into thepost-processing system, and on the basis of this information, make diskspace available on its mass storage for new data.

The post-processing system comprises a program which compares thecontrol file of the exchange or the communication device to the controlfile of the system, and which updates the control file of its own andcarries out the required FTAM file transfers. Between the entirepost-processing system and the exchanges, there exists a commonagreement on the naming principles.

With reference to FIG. 2, the following illustrates how the method ofthe invention works in practice by a FTAM protocol.

In the example of FIG. 2, the names of the data files to be stored inthe mass storage of the communication device (DX) consist of atwo-letter first part DF and a four-digit file serial number, forexample, 0002. The extension part of the file consists of the letter Dand a two-digit number associated with the number of the mass storagedevice. The number of the first data file is one (1), and the number ofthe last file naturally corresponds to the total number of files. If,for example, the memory 3 includes 500 data files each of which of 10kilobytes and which have DF as the first part of their name, thedirectory includes files DF0001.D03 , DF0002.D03, . . . DF0500.D03 whichtake up 5 megabytes of disk space in all.

The data files are located in a separate directory on disks of the DX200 system. They are automatically created one by one as the need arisesin normal operation. Each mass storage of the communication devicecomprises two control files, TTTCOF and TTSCOF. The records of thecontrol file TTSCOF for data storage of the communication device itselfcomprise the status and time stamp of the data files associated withthem, which time stamp indicates the latest updating of status. Therecords of the control file TTTCOF for data transfer, maintained by thepost-processing system OS, only comprise time stamps on the data filesthat have been transferred. Each record of a control file is associatedwith the data file having the same sequence number.

In the TTSCOF control file, the status of data files is described asbytes. The possible values for them are, as described above, open (00H),full (01H), and transferred (02H). The time stamp consists of sevenbinary coded decimal bytes. The following will illustrate the structureof a time stamp with an example.

                  TABLE 1                                                         ______________________________________                                        Structure of time stamp.                                                                              23rd March 1992                                       BYTE        STAMP       10:35:42                                              ______________________________________                                        0           seconds     42H                                                   1           minutes     35H                                                   2           hours       10H                                                   3           days        23H                                                   4           months      03H                                                   5           years (tens)                                                                              92H                                                   6           years (thousands)                                                                         19H                                                   ______________________________________                                    

The first record (number zero) of either one of the files TTSCOF andTTTCOF is not associated with data files. The zero record of TTTCOFplays no role. The TTSCOF zero record comprises a write pointerindicating where the next data to be received are to be written. Thefirst word of the TTSCOF zero record includes the number of the datafile currently open, and the following double word comprises the offsetpoint of the data file. The last word is not in use.

Apart from the communication device DX, also the post-processing systemOS can read (arrow C) the control file TTSCOF of the communicationdevice. The integrity of the system is achieved by limiting the writingright so that only the communication device is given the right to writeinto the TTSCOF file, and only the post-processing system is given theright to write into the TTTCOF file (arrow B).

By comparing the contents of the control files, the communication deviceDX or the peripheral device interface OMC can infer which files havebeen transferred to the operating system, which files are full of data,and which file is currently open. The next data file to be opened is theoldest of the transferred files and thus the new data are written overthe previous data of the file which was opened. In this way, the diskspace which the system uses for storing data remains reasonable.

The post-processing system advantageously utilizes a polling cycleduring which it reads (arrow C) the contents of the TTSCOF file of datastoring by using FTAM procedures. After this, it compares the TTSCOF tothe contents of the TTTCOF copy which is in the postprocessing system.On the basis of the time stamps and the status data, the system inferswhich data files must be transferred because they have, for example,become full. Having successfully transferred (arrows A) data files bythe FTAM protocol, the post-processing system updates the TTTCOF file bywriting into it the names of the files that have been transferred andthe time stamp of the transfer. After this, the updated TTTCOF is copied(arrow B) to the DX 200 system by using the FTAM protocol.

The user can determine that the transferred files are stored in the massstorage of the communication device (DX) for at least a certain time. Iffor this reason, or due to a malfunction in the post-processing system,the number of data files available for overwriting, i.e. the usable massstorage capacity, falls below a predetermined level, an alarm is given.

It is obvious for a person skilled in the art that the embodiments ofthe invention are not restricted to the examples above but may freelyvary within the scope of the attached claims. Thus, a communicationdevice does not here refer only to switching exchanges, but to anydigital data transfer device which collects data to a memory of its ownfor later transfer to centralized post-processing.

I claim:
 1. A method for transfer of files produced by a communicationdevice from a mass storage of the communication device to a memory of apostprocessing system for the data contents of said filescomprising:maintaining a control file (TTSCOF) of the communicationdevice by marking the control file with information as to the state ofeach file in the mass storage of the communication device, a time stampof the latest writing operation into the file; reading said control fileinto the post-processing system, and comparing said control file toanother control file (TTTCOF) which is in the memory of thepost-processing system and which is updated during each transfer;reading into the post-processing system those files of the communicationdevice (DX) that, on the basis of the comparison of control files(TTSCOF, TTTCOF), have been modified since the latest updating of thecontrol file of the post-processing system; updating the control file ofthe post-processing system (TTTCOF) by marking said control file withinformation as to the files that have been transferred, and copying saidinformation to the communication device (DX) for indicating the capacitymade available in the mass storage of the communication device.
 2. Amethod as claimed in claim 1, the control file of the postprocessingdevice is updated by marking it with information on the files that havebeen transferred and the date of the transfer for each file.
 3. A methodas claimed in claim 1, the files to be transferred, as to their status,are files that have become full.
 4. A method as claimed in claim 1, thefiles to be transferred are all the files which have been modified sincethe latest updating of the control file (TTTCOF) of the postprocessingsystem.
 5. A method as claimed in claims 1, the operating system (OS) ofthe post-processing system carries out at predetermined intervals apolling during which it reads the contents of the control file (TTSCOF)of the communication device (DX) and compares the contents to thecontents of the control file (TTTCOF) which is in the memory of thepost-processing system in order to determine the need for transfer offiles of the communication system.
 6. A method as claimed in claim 1,thefiles that have been transferred are stored in the mass storage of thecommunication device (DX) at least for a certain time, whereby an alarmis generated if the number of data files available for overwriting fallsbelow a predetermined threshold level.